The connection between iron and vitamin C lies in the fact that iron absorption is significantly increased by the presence of vitamin C, also known as ascorbic acid. Iron and vitamin C also also work together in that vitamin C plays a vital role in the synthesis of red blood cells, and iron is a vital component of hemoglobin which is found in red blood cells. Another connection is evident when considering that vitamin C is essential for the integrity of the blood vessels of the body: veins, venules, arteries, arterioles and capillaries.

Although vitamin C greatly increases iron absorption, this is true only when speaking of the ingestion of all-natural iron from foods rich in the mineral, such as green leafy vegetables or whole heirloom grains such as spelt. The iron and vitamin C connection does not exist when the iron ingested is from a supplement, including a multivitamin or mineral supplement. Equally important for the increase in iron absorption is the need to consume foods that are rich in vitamin C, such as citrus fruits or greens, at the same time of consuming iron-rich foods. Pure pharmaceutical-grade ascorbic acid, which comes in the form of a powder, can be taken at a meal containing iron-rich foods.

Red blood cells are responsible for the transportation and delivery of oxygen to every tissue in the body in order to keep them alive and healthy. These functions are made possible by hemoglobin, which is a compound located in red blood cells that contains iron. Vitamin C is essential for the production of red blood cells, and iron is richly found in hemoglobin, so iron and vitamin C clearly contribute to the processes involved with all tissues of the body receiving adequate amounts of oxygen and also with ridding themselves of carbon dioxide. The connection between iron and vitamin C is further realized when one considers the importance of the integrity of blood vessel walls.

Vitamin C is essential for the integrity of the walls of blood vessels, and iron is found in hemoglobin — the compound in red blood cells that circulate through those blood vessels — so the connection between iron and vitamin C can be viewed as a very close one. Females and people suffering from poor circulation or iron-deficiency anemia are advised to be well informed of the connection between iron and vitamin C. Roughly only 10 percent of the iron ingested through food is actually absorbed when the body is not deficient of the nutrient. As much as 35 percent is absorbed when there is a deficiency. That percentage can be increased even more if care is taken to ingest vitamin C during iron-rich meals, keeping in mind the importance of the connection between iron and vitamin C.